Installing replacement Avocet seat

I need to replace the seat in my poly Avocet. What’s the best way of getting seats in and out of this boat?

It’s a very, very tight fit and I’m concerned about breaking the new seat. It needs to be put in and taken out a few times while I’m shaping the foam supports underneath it to the appropriate height.

rotate it
Rotate it within the boat. Seat is quite sturdy, so are the sides of the boat.

There is expanding marine foam, TAP X-30 Polyurethane Foam, that might make your project go faster.

I think I was being too hesitant about bending the seat and coaming for fear of cracking the seat. Also found that the foam blocks can’t be in place on the seat when putting it in or taking it out so the foam will have to be added after it’s in place. Appreciate the advice.